Porphyrias

Question 1

three porphyria disorders

Answer 1

1. acute intermittent porphyria
2. Porphyria Cutanea Tarda
3. Lead Poisoning

Question 2

acute intermittent porphyria has defect in which enzyme and requires the induction of which enzyme

Answer 2

PBG deaminase; ALAS

Question 3

porphyrias

Answer 3

are disorders with deficiencies with enzymes that help make heme; cause buildup of porphyrins (metabolites); usually inherited

Question 4

PBG deaminase completes which reaction

Answer 4

occurs in the cytoplasm

PBG (porphobilinogen) –> HMB (hydroxymethylbilane)

Question 5

porphyria can lead to

Answer 5

facial hair and red glowing teeth

Question 6

What is the committed enzyme for formation fo heme?

Answer 6

ALAS

Question 7

What induces ALAS activity?

Answer 7

1. hepatic depletion of heme
2. metabolic stress
3. drugs
4. hormones
5. smoke

Question 8

clinical presentation of AIP ?

Answer 8

1. increased catecholamines which can increase heart rate and lead to hypertension
2. CNS- seizures
3. GI pain without inflammation
4. insomnia
5. acute and intermittent
6. SIADH- hyponatremia (low sodium)
7. red or dark urine when exposed to sunlight

Question 9

ALAS reaction

Answer 9

succinyl CoA + glycine –> ALA

Question 10

acute intermittent porphyria has what type of inheritance

Answer 10

autosomal dominant

Question 11

acute intermittent porphyria is low or high penetrance

Answer 11

low

Question 12

laboratory findings

Answer 12

1. increased ALA and PBG

2. decreased activity of PBG deaminase

Question 13

treatment

Answer 13

1. stop induction so medication, smoking, drug, metabolic stress
2. increase carbohydrates
3. glucose 10 %
4. hematin

Question 14

hematin inhibits which enzyme

Answer 14

ALAS

Question 15

prolonged attacks of AIP can lead to which peripheral neuropathy motor symptoms

Answer 15

1. bulbar paralysis
2. respiratory impairment
3. death

Question 16

exacerbating factors of AIP?

Answer 16

1. decreased carb diet
2. drugs
3. hormones
4. metabolic stresses- infections, surgery, psychological stress
5. cigarette smoke

Question 17

Porphyria Cutanea Tarda is caused by

Answer 17

deficiency of UROD (uroporphyrinogen decarboxylase)

Question 18

UROD uroporphyrinogen decarboxylase reaction

Answer 18

uroporphyrinogen III –> coprophyrinogen III

Question 19

what leads to reduced activity of the enzyme

Answer 19

iron overload

Question 20

______ is correlated with clinical expression of this disease

Answer 20

hepatic iron levels

Question 21

three associated disorders

Answer 21

1. alcoholism
2. hemochromatosis
3. hep C

Question 22

when uroporphyrinogen is made in the _____ it is deposited in the _______ as a metabolite and causes ____

Answer 22

liver; skin; blisters and rash

Question 23

patients with PCT are at increased risk for

Answer 23

cirrhosis and heptacellular carcinoma

Question 24

diagnosis

Answer 24

clinical

- normal levels of ALA and PBG

Question 25

PCT treatment

Answer 25

- remove all offending agents (alcohol, smoke and estrogen) - sunscreen and sun exposure protection - phlebotomy

Question 26

lead poisoning is microcytic or macrocytic

Answer 26

microcytic

Question 27

lead poisoning in children is usually via ______ and in adults via ______

Answer 27

ingestion; inhalation

Question 28

forms of lead

Answer 28

- moonshine - makeup - gas - paint - water

Question 29

clinical signs of lead poisoning

Answer 29

- lead line - decreased libido - muscle joint pain - wrist and foot drop - microcytic anemia - GO effects- crampy abdominal pain (lead colic) constipation

Question 30

diagnosis

Answer 30

- blood test | - venous for children

Question 31

treatment

Answer 31

- reduce lead exposure | - chelation therapy

Question 32

lead poisoning level for children ___ | lead poising for adults

Answer 32

5 10 should be 0

Question 33

once in the body 99% of lead is bound to

Answer 33

RBS

Question 34

lead biochemical effects

Answer 34

inhibits ALAS and ferrochelatase

Question 35

ferrochelatase

Answer 35

last enzyme that formation of heme adds the Fe

Question 36

blood smear for lead poisoning shows

Answer 36

basophilic stippling

Question 37

lead exposure chronic effects

Answer 37

1. hypertension 2. neuropsychiatric effects 3. mortality 4. reproductive effects 5. lead neuropathy 6. saturnine gout

Question 38

chelation therapy

Answer 38

should not be used unless exposure has been definitively curtailed since in the presence of continuous exposure it can cause increased absorption

Question 39

atkins diet

Answer 39

low carb diet that can induce ALAS